Billions of dollars spent on defeating improvised explosive devices are beginning to show what technology can and cannot do for the evolving struggle

Two platoons of U.S. Army scouts are in a field deep in the notorious ”Triangle of Death” south of Baghdad, a region of countless clashes between Sunni insurgents and Shia militias. The platoons are guided by a local man who’s warned them of pressure-plate improvised explosive devices, designed to explode when stepped on. He has assured them that he knows where the IEDs are, which means he’s almost certainly a former Sunni insurgent.

The platoons come under harassing fire. It stops, but later the tension mounts again as they maneuver near an abandoned house known to shelter al-Qaeda fighters. A shot rings out; the scouts take cover. They don’t realize it’s just their local guide, with an itchy trigger finger, taking a potshot at the house. The lieutenant leading the patrol summons three riflemen to cover the abandoned house.

Then all hell breaks loose. One of the riflemen, a sergeant, steps on a pressure-plate IED. The blast badly injures him, the two other riflemen, and the lieutenant. A Navy explosives specialist along on the mission immediately springs into action, using classified gear to comb the area for more bombs. Until he gives the all clear, no one can move, not even to tend the bleeding men. Meanwhile, one of the frozen-in-place scouts notices another IED right next to him and gives a shout, provoking more combing in his area. Then a big area has to be cleared so that the medevac helicopter already on the way can land. The sergeant dies several hours later in a field hospital.

That incident, which took place on 7 November 2007, exhibits many of the hallmarks of the missions in Iraq and Afghanistan—a small patrol; a local man of dubious background; Navy specialists working with soldiers on dry land; and costly technologies pressed into service against cheap and crude weapons.

And, most of all, death by IED.

”Sergeant T” became one of the 24 coalition soldiers killed by IEDs that month in Iraq. As of the end of June, IEDs have killed untold thousands of Iraqis and Afghanis, as well as 1795 coalition military people in Iraq and another 231 in Afghanistan, according to the Web site iCasualties.org. Those figures are nearly half of all combat fatalities in Iraq and roughly 30 percent of those in Afghanistan, according to the site.

IED fatalities in Iraq were down sharply in May and June, to 14 and 11, according to iCasualties. But they were up in Afghanistan, to 12 in May and 22 in June. Overall, in the first half of this year, IEDs, including suicide bombs, killed 115 coalition people in Iraq and 72 in Afghanistan. Those figures mean that in the first half of 2008, IEDs caused 54 percent of all coalition deaths (including nonhostile ones) in Iraq and 59 ­percent in Afghanistan.

The U.S. military has responded with the most intensive program of technology development in at least a decade. It has spent US $12.4 billion over the past three years on counter-IED equipment, technology R&D, training, and other measures through the Joint Improvised Explosive Device Defeat Organization and its predecessors.

JIEDDO says that its mission is to support efforts to defeat IEDs as ­”weapons of strategic influence.” This wording acknowledges that insurgent fighters use IEDs with no hope of defeating a military force in the traditional sense. The point is to cause death and destruction resulting in news imagery that affects the politi­cal will of the country that dispatched the force. This distinction is significant because it implicitly suggests that IEDs and the casualties they cause cannot be eliminated. It points to a response based on minimizing their effectiveness, for example with armor and by other means, to marginalize their strategic impact.

JIEDDO emphasizes a holistic approach, incorporating such nontechnical aspects as training troops in ­counter-IED tactics and technology and using law enforcement techniques, forensics, and intelligence to smash the networks that build and deploy IEDs. But this year, $2.57 ­billion of JIEDDO’s $4.38 ­billion budget is devoted to developing ­counter-IED technologies, feeding a perception that the agency is chasing a cure-all.

Editor’s note: To minimize the possibility that information in this article could endanger coalition personnel in Iraq or Afghanistan, a draft of this article was reviewed by current and former officials of the Joint IED Defeat Organization, a U.S. Department of Defense agency. In response to those reviews, IEEE Spectrum voluntarily removed three passages and the names of two active-duty U.S. military personnel.

RIGHT OF BOOM

Jose Callazo’s Husky mine-detecting vehicle hit a buried IED south of Baghdad on 4 August 2007. Callazo was treated by medics [top] and recovered from his injuries. A vehicle-borne IED outside a newspaper office in Baghdad’s Waziriya district [center] killed two people, injured 30, and destroyed more than 20 cars. A soldier paid tribute [bottom] in 2006 to a comrade killed by an IED.

In an interview, a civilian at a military academic institution who studies counter-IED tactics characterized the U.S. approach as ”hide and pray: hiding behind more armor and praying that there’s a technical solution to all this.”

Three U.S. military officers offered more specific criticisms in a recent paper for the Joint Forces Staff College, in Norfolk, Va. JIEDDO, they wrote, ”is still built around a technical-solution approach focused on research and development, testing, and fielding the elusive ’silver bullet’ to defeat IEDs.”

There are lots more published criti­cisms in that vein. Nevertheless, it’s basically impossible to find anyone inside or outside of JIEDDO who believes in a ”silver bullet” technology that will solve the IED problem. On the other hand, it’s not too hard to find people who think that technologies—including ones that predict or detect IEDs as well as others that neutralize them or at least lessen their effects--will be part of a complicated and variable set of responses that reduce the lethality of IEDs and also increase their costs to the extent that they become ineffective.

The challenge is more complex than most people realize. ”There have been no easy problems when it comes to measure-countermeasure, whether you’re talking about submarine warfare–antisubmarine warfare, tank-antitank, or antiaircraft-counterantiaircraft,” says Daniel Gouré, vice president of the Lexington Institute, an Arlington, Va., think tank. ”They’re always immensely complicated challenges in which technology just plays a piece.

”Overall,” Gouré adds, ”the effort to counter the IED has been a real lesson in humility to a military that has always prided itself on being able to find a technical solution to a problem.”

The U.S. experiences in Iraq and Afghanistan have pretty much confirmed that technology alone can’t solve an IED problem. U.S. forces did not see steep declines in IED incidents in parts of Iraq until they gained the cooperation of local people in those areas and secured their help in aggressive efforts to attack the terrorist networks that put IEDs on the roads.

The problem is that in war or its aftermath, the active support of local people can seldom be counted on. And IEDs are already a problem in places where there is no occupation, where no war is being fought, and where there is no antagonistic local population to be won over.

It’s not easy to assess counter-IED technology’s capabilities and limits, because researchers are pursuing hundreds of projects, many of them are classified, and some have yet to prove themselves outside of a laboratory. Nevertheless, with the United States and other countries pouring billions of dollars into ­counter-IED activities, a couple of questions come to mind: how much can technology do, in the absence of local cooperation, to reduce casualties from IEDs? Can some combination of the technologies now being pursued, together with nontechnical approaches such as intelligence exploitation, suffice to marginalize the strategic influence of IEDs?

The alternative scenario is not pretty. In it, the IED continues for the foreseeable future to be the weapon of choice for the world’s terrorists, insurgents, ­militias, guerillas, revolutionaries, and marginal or failed states.

The stakes are high. The scale and urgency of the struggle to devise an effective response reflects not just the deaths in Iraq and Afghanistan but also an almost universal consensus among military analysts and government officials that the IED problem will long outlive those conflicts. Lots of facts support that view, but start with this one: outside of Iraq and Afghanistan, there are 200 to 350 IED attacks every month around the world, according to the Triton report, which is published periodically by the British counter-IED consulting firm Hazard Management Solutions. IED attacks are particularly common in Colombia, India, Indonesia, Pakistan, the Philippines, Russia (Chechnya), and Sri Lanka.

In Pakistan alone, IEDs, including suicide bombs, killed 865 security people and officials last year, according to testimony in the U.S. Senate in February. In 2006, British officials dealt with 250 IEDs in the UK, according to Andy Trotter, deputy chief constable of the British Transport Police. They were planted by ”criminals, animal rights activists, disturbed individuals, and terrorists,” Trotter says.

IEDs aren’t new. In World War II, Belorussian guerillas used them against the German army. The Vietcong made them out of unexploded U.S. ordnance during the Vietnam War. The mujahideen used IEDs in Afghanistan in the 1980s against the Soviets.

BOMB-MAKING MATERIALS

A tip in March 2007 led Iraqi police to a cache of IED-making parts in Anbar province. U.S. soldiers inspected the haul [top], which included bags of blasting caps. An Iraqi Army raid turned up other IED items [lower left], including wires for triggering bombs at a distance. In February 2007 [lower right], U.S. soldiers found copper liners and enough other components to make 150 explosively formed penetrators, a particularly deadly form of IED. The materials were found in a Shia village north of Baghdad.

But it was the Irish Republican Army that first demonstrated the level of havoc that homemade bombs could create in a sustained campaign. Over 37 years, from the early 1970s until the late 1990s, the IRA targeted infrastructure and British soldiers and achieved ”a complete spectrum of development of the IED from simple, crude devices to quite sophisticated devices,” says Lt. Col. Jim Storr, a British Army veteran. In the early 1970s, the British Army was dealing with as many as 1400 IED detonations a year, Storr says.

That’s how many occur in Iraq and Afghanistan in three or four months.

The prevailing theory on the future of warfare contends that recent and ­ongoing conflicts—in Afghanistan, Bosnia, Iraq, Israel, Lebanon, Sudan—are just the opening phases of what will be a decades-long era of scattered, low-­intensity engagements that will pit advanced countries against a constantly changing assortment of nonstate militias and marginal or failed states. The conflicts will be ­”asymmetric,” meaning that the fighting won’t involve vast arrays of tanks, fighter planes, and bombers, radar and countermeasures, and troops firing ordnance at each other in accordance with military doctrine as it has evolved over the past 2500 years. Given their goals and the means available to them, and their need to counteract their opponents’ overwhelming advantages in technology and resources, insurgents and militiamen will keep on using IEDs, including car and suicide bombs.

To be specific: ”The IED threat will be long-term, because nobody will want to fight the United States force-on-force,” predicts Col. Dick A. Larry, head of the IED division of the U.S. Army Asymmetric Warfare Office.

”IEDs have the capability to inflict damage, political and psychological, out of all proportion to their size and cost,” noted Maj. Gen. Anthony Stone, the former director of special projects for the UK’s Ministry of Defense, at a recent conference on ­counter-IED technology.

Some analysts warn that rogue fighters will inevitably use weapons of mass destruction, probably in an improvised way. And though the United States and some European and Asian countries have seen few IED attacks so far, not many analysts think that state of affairs will go on indefinitely.

”If we do not find solutions now in Afghanistan and Iraq, we will continue looking for solutions when this problem comes to the United States,” says Colonel Barry L. Shoop, who is director of the electrical engineering program at the U.S. Military Academy and was JIEDDO’s first chief scientist.

The difficulty of the counter-IED challenge arises from many factors. The physical, electromagnetic, and chemical environments in which IEDs are deployed are chaotic and cluttered. The social networks that let insurgents fund, build, and emplace IEDs are incredibly complex. And IEDs themselves are hugely diverse, their makers having proved themselves tireless in adapting and altering their creations.

All IEDs have a power source, a trigger, a detonator, and a main charge. The power source is usually a battery. Its function is to supply enough energy to the detonator, usually a blasting cap, to enable it to set off the main charge. In 2004, as IEDs began proliferating wildly in Iraq, the main charge was typically artillery rounds lashed together to explode simultaneously, the casings shattering to provide shrapnel. Bomb makers also frequently pack ball bearings around the main charge to maximize casualties.

Over the past couple of years, Sunni insurgents have favored homemade explosives for the main charge. They’re more easily used in the huge quantities needed to fling through the air the 25-ton vehicles now commonly used by U.S. forces. The typical homemade explosives in Iraq, urea nitrate and ammonium nitrate, are produced using nitrogen-based fertilizers. To make urea nitrate, bomb makers separate the urea from the fertilizer and then use nitric acid to attach a nitrate group (NO 3 ) to the urea molecule.

The fertilizers and other materials are not easily controlled, because Iraq’s struggling economy has a large agricultural component. And even with hundreds of IED incidents a month in Iraq, the relative amount of fertilizers diverted to making IEDs is small.

Five-gallon cans or barrels are common containers for the main explosive. For a barrel, the detonator might be a bag filled with TNT and a blasting cap (ironically, the bag has often been the thick plastic bag that a military ”meal, ready to eat” comes in). To complete the IED, a trigger of some sort is connected to the detonator. Such a bomb could easily destroy a light vehicle like a Humvee or could seriously damage a heavier, more extensively armored vehicle, such as an MRAP (mine- resistant, ambush-protected) truck.

The two most lethal forms of IEDs are deep-buried IEDs and explosively formed penetrators (EFPs). They account for only 5 to 15 percent of all IEDs in Iraq but roughly 40 percent of the IED casualties, according to the latest figures from the U.S. Defense Department. Deep-­buried IEDs often contain hundreds of kilograms of explosive and have flung heavily armored vehicles like MRAPs tens of meters, in one case killing all on board.

IED ATTACKS are already common in some places outside of Afghanistan and Iraq [top]. The rate of attacks in Iraq [bottom] declined in the first half of 2008, thanks to aggressive efforts to dismantle the networks that build and deploy IEDs. (The number of incidents is not included in this chart because the Joint IED Defeat Organization declined to release them.)

We went into an intersection, and the EFP went off and went right through our vehicle,” says the deputy commander of the Gulf Region Central District of the U.S. Army Corps of Engineers in Iraq. At the time of the attack, he was south of Baghdad, in a heavily armored vehicle called a Wolf. ”The molten metal came up underneath us, and there were a few shrapnel pieces that were inside the compartment. But, for the most part, it missed us.” Even so, he was bleeding internally so badly that he had to be flown to Germany, where his life was saved by an 8-hour operation that put in 600 internal stitches. It was the fifth IED attack he’d survived, and by far the worst.

It was a classic explosively formed penetrator attack: the target was an armored vehicle, and the projectiles were fired at close range, in this case from below the vehicle.

EFPs are associated particularly with Shia militia groups. The U.S. military has long contended that Iran is a supplier of the EFP’s key component—a concave copper disk, called a liner, that must be properly machined to work well. This disk is fitted to one end of a metal tube that’s slightly longer than the diameter of the disk. The tube is packed with a plasticized military explosive, typically one containing cyclotrimethylenetrinitramine, also known as RDX. Its detonation releases an extremely fast-moving shock wave, which turns the liner into hot, explosively formed fragments moving at one to two kilometers per second—faster than a high-velocity rifle round. The kinetic energy of the fragments is so high that it penetrates most kinds of armor.

EFPs are usually triggered by a ­passive infrared sensor. The triggering system also often has a radio-control override that lets the triggerman enable the system when he sees a vehicle coming that he wants to attack. The infrared sensor then detects the heat of the passing vehicle and detonates the device. The U.S. military has contended that the radio-control systems also come from Iran.

The EFP is a textbook case of ­measure-countermeasure–counter-countermeasure. For a time, coalition vehicles sought to throw off the EFP’s infrared trigger with a simple counter­measure called a rhino, basically a hot glow plug in a metal can affixed to the front of the vehicle by a rod of variable length. It reduced the effectiveness of EFPs but not decisively so, because the attackers varied the timing of the detonation to try to counteract the rhino.

The triggering system, generally the only complicated part of an IED, remains the focus of strenuous countermeasures because it is pretty much the only component you can attack with technology. Early on, in 2003 and 2004, most IEDs in Iraq and Afghanistan were triggered wirelessly, often with cellphones, long-range cordless phones, key fobs, walkie-talkies, and wireless doorbells.

Relying on modified existing hardware and Navy expertise, JIEDDO’s predecessor quickly fielded jamming ­systems. Installed in vehicles, the jammers provide a bubble of safety around the vehicle, within which radio-frequency power overwhelms any signal being transmitted to an IED’s wireless trigger.

The jammer program became known as CREW, for ”counter radio-controlled IED electronic warfare.” The latest jammers designed for U.S. vehicles are code-named Jukebox and CVRJ and are manufactured by EDO Corp. and other companies. They cost upwards of $80 000 apiece. All told, the U.S. military spent about $2 billion on jammers in 2007.

The insurgents’ response to the first jammers, in late 2003, was swift. It established a Spy vs. Spy –like competition between counter-IED specialists and the bomb makers, in which sometimes a measure was followed by a counter­measure within days.

As jammers proliferated, insurgent groups quickly went back to using command wires—buried pairs of long enameled copper wires attached to a simple switch—and also to ”victim-operated” triggers. These triggers, also usually buried for concealment, include pressure plates and crush wire—flexible tubing with two conductors inside that touch and make an electrical connection when the tubing is squashed by a tire or a foot.

Photo: Petros Giannakouris/Ap Photo

IED AFTERMATH

A mine-resistant, ambush-protected truck hit a roadside bomb on an Al Talbiyah street in Baghdad on 19 June. The heavily armored vehicle was significantly damaged, but no one was hurt.

Defeating the device ” is how JIEDDO refers to the many things it does to deal with an IED already in place: searching for it, disposing of it, and if all else fails, surviving its blast. These tasks get a lot of attention because the score is easily tallied. Column A: lives saved; column B: lives lost, damaged, irrevocably changed. But defeating the device is actually a small piece of a much larger and evolving counter-IED strategy.

JIEDDO originally divided its projects among five functions: prediction, detection, prevention, neutralization (which includes defeating the device), and mitigation. Some of those technologies and most of the techniques, as deployed today in Iraq and Afghanistan, are classified. Still, what is known about those categories offers at least a partial view of evolving counter-IED strategies, as well as insights into the main issue: whether the strategic influence of IEDs can be subverted.

In this world, simply categorizing activities can be complicated. A few years ago, when it became clear that going after IEDs on the road wasn’t having the desired effect, the rallying cry became ”attack the network”—in other words, destroy the infrastructures that build and deploy IEDs. Attacking the network, it turns out, spans prediction, prevention, and part of detection.

JIEDDO has been criticized for spending too little on attacking the network. But as a former JIEDDO official wrote in an e-mail, ”a significant portion of the activities in Attack the Network are classified,” making it difficult for outsiders to know how big the effort actually is.

Attacking the network boils down in part to analyzing social networks, collecting and analyzing intelligence, and persistently surveilling places. It has been a difficult challenge, depending as it has on wildly incongruous data, tips, and reports from surveillance systems, such as unmanned aerial vehicles, and from local people suspicious of activity in their neighborhoods. ”It’s a challenging new frontier,” says Shoop. ”Combining an ­understanding of the psychology and sociology of terrorist networks with probabilistic modeling, complexity theory, forensic science, pattern recognition, and data mining to predict human behavior is new.”

JIEDDO has already acknowledged that it is using sophisticated database software in Iraq to help its analysts get a handle on that multifarious assortment of images, data, intelligence, and anecdote that bears on whether an IED has been emplaced. In his final press conference this past November as director of JIEDDO, retired U.S. Army Gen. Montgomery Meigs identified for the first time an organization called the Counter IED Operations Integration Center. Calling it a ”very powerful intelligence fusion operation,” he added that ”it makes a difference in that line of operations we call ’attack the network.’ Beyond that, I can’t say anything.”

Meigs’s successor at JIEDDO, Lt. Gen. Thomas F. Metz, said in an interview this past May: ”Say you know a particular part of your district gets a larger proportion of IEDs. You want to study it, layer in all the data: signals intelligence, significant events over a couple years, moving target indicators from JSTARS [an advanced military reconnaissance aircraft], humint [human intelligence] reports. You have to take it on faith from me that actionable patterns begin to form.”

Life and death on the roads of Iraq and Afghanistan often depend on the eyes and intuition of soldiers just a few years out of high school. Most IEDs are found today by a soldier peering through a thick Lexan window of a massively armored truck and noticing something amiss.

”You won’t find the IED itself,” explains a U.S. Army counter-IED trainer, in an interview at Camp Speicher in Tikrit, Iraq. ”You look for other indicators. Trash right after a route clearance. Disturbed soil. An area strangely devoid of activity, or a heavily laden vehicle with no occupants. A donkey cart by itself—it’s somebody’s livelihood, so why is it abandoned? Why is no one there?”

Over the past year in Iraq, military patrols guided by local people, often former insurgents, have uncovered countless thousands of IEDs. The locals are paid to reveal where the bombs are.

Soldiers travel the roads in RG-31s, MRAPs, convoy trucks, and Buffaloes, which have a big robotic arm that can be operated from inside to paw through roadside junk. Many of the vehicles are also outfitted with a Gyrocam, a gyrostabilized telescopic camera system that lets them scrutinize, on a monitor in the truck, suspicious roadside objects from hundreds of meters away. The system can be switched to one of three different bands: visible light, infrared, and thermal (the thermal mode is useful for turning up people hiding at night), and it costs more than $500 000. It is used on drone aircraft such as Predators as well.

Other technologies also help with detection. A vehicle called a Husky has a powerful magnetometer that detects buried metal-containing objects, such as pressure plates, crush wire, and artillery rounds. At the moment of detection, though, the driver is directly above the object. To protect the driver as much as possible in a blast, the Husky has a cast-metal suspension and a harness restraint system designed for a helicopter. Those features have let drivers walk away after being blown 20 meters in the air.

Drone aircraft also sometimes spot evidence of IEDs or even catch insurgents in the act of installing them. In tactical operations centers all over Iraq you can see video from Warrior, Shadow, Predator, or Hunter aircraft playing out on flat-panel monitors in real time. Mostly, the feeds show empty or cluttered roads and suggest the immensity of the detection challenge.

Nevertheless, a special C-IED U.S. Army task force called ODIN (for observe, detect, identify, neutralize) has for more than two years been using a small fleet of piloted and drone aircraft to monitor the main supply routes in Iraq. A New York Times report in June said the task force had about 300 people and 25 aircraft assigned to it. When they spot people placing IEDs, ground controllers feed the information to quick-response combat teams, with often fatal results for the bombers.

In an interview with the newsletter Defence Systems Daily last November, Maj. Gen. James E. Simmons said that as of August 2007 the program had resulted in the deaths of 233 IED emplacers, the injury of 48 others, and the detainment of 260. To put those numbers in perspective, in a typical month a single turbulent province like Salah Ad Din could, until recently anyway, record more than 800 IED incidents.

For the record, most of the armored vehicles listed above, as well as the Gyrocam and ODIN, were all at least partially funded initially by JIEDDO.

It’s really hard to find tiny wires in the dirt,” said General Meigs in his final JIEDDO press conference last November. ”And it’s hard to find an IED that’s buried. Those are tough challenges from a laws-of-­physics perspective.”

Tough, but maybe not impossible. Dozens of advanced-tech projects are aimed at detecting buried IEDs. Some systems are intended to fly aboard drone aircraft, others to be carried on vehicles; still others are to be carried by a soldier. In the airborne category are advanced imaging systems that would find buried IEDs, pressure switches, and even command wires by detecting disturbed earth. These systems, being developed by several defense contractors, would sense radiation in dozens of narrow spectral bands in the visible and infrared parts of the spectrum.

The principle is that disturbed earth scatters radiation differently from undisturbed earth. The system, called a hyperspectral imager, would run algorithms to calculate the signal strength in those spectral bands. That data would be used to map, for a grid of points on the ground, the reflectance as a function of wavelength. Limited processing power forces a tradeoff between the spatial resolution on the ground (you want to be able to see command wires) and the spectral resolution (you need a certain minimum number of spectral bands to reliably detect disturbed earth). The systems being tested now use bright, contrasting colors to show subtle differences in reflectance.

Another project, now being tested, detects command wires using a radio transmitter, carried by a soldier, that sweeps through a wide band of frequencies. The waves are polarized, and when the polarization is properly aligned with a length of buried wire, the radio-frequency energy couples into the wire. That coupling causes a resonance at a specific frequency. The system detects that resonance, which can indicate not only the presence of the wire but also its approximate length.

Troops are also testing detection systems that use ground-penetrating radar or other technologies to detect command wires. JIEDDO has publicly identified two such projects, code-named Desert Owl and Copperhead, but has not released any details.

There is also a lot of work on systems that can detect IEDs at what are called standoff distances: tens of meters, or far enough to survive if the IED blows up. A couple of years ago troops in Iraq were reportedly using a system called PING, which emitted microwave signals that penetrated building walls. If the signals encountered an IED with large amounts of metal, the IED altered those signals in a way that could be detected, presumably with reasonable consistency.

Some of these standoff systems depend, or will depend, on radically new technologies, such as terahertz-frequency and millimeter-wave radiation [see Web-only sidebar ”Terahertz Waves: No Silver Bullet”], or on radical applications of existing technology. Several have already been deployed, with limited success, but most are more than a few years away. The existing technologies include visible light lasers, ground-penetrating radar, synthetic-aperture radar, thermal imaging, magnetic resonance, and electronic ”sniffers” that can detect in the air infinitesimal concentrations of molecules from explosives.

A sniffer called Fido is being used in Iraq and Afghanistan; there’s a handheld version and also one attached to a small robot. Fido exploits a kind of material called an amplifying fluorescent polymer. A polymer is a long chain of identical molecular links called monomers. When a photon hits a fluorescent polymer, it releases an excited electron that travels along the chain, causing the monomers to fluoresce. The monomers are designed, however, so that if any one of them encounters and binds with a certain molecule—let’s say one from a nitroaromatic explosive—the fluorescence is quenched.

Because the chain has so many potential receptor sites, the system based on it can detect concentrations down in the parts-per-quadrillion range, according to the original paper on the invention, which was published in the June 2001 IEEE Transactions on Geoscience and Remote Sensing . But although the Fido system works well, it does so only for a limited number of explosives, according to an official familiar with it. And the only standoff capability you get is from the robot.

Neutralizing an IED means either disabling it or destroying it. Both jobs are performed by military specialists trained in the rapidly expanding discipline known as explosive ordnance disposal, or EOD.

U.S. EOD teams travel in 26-ton ­technology-stuffed trucks called Joint EOD Rapid Response Vehicles (JERRVs) that cost more than $1.2 million fully equipped (the JERRV was also a JIEDDO project). The teams, usually made up of two or three people, strive to disable and recover unusual IEDs because of their intelligence value. Those recovered IEDs, as well as forensic evidence gathered at places where IEDs have detonated, are sent to a laboratory near Baghdad airport for analysis. IED specialists say that years of work at that lab have enabled them to know, in many cases, such details as exactly who built an IED and possibly where he built it.

If the IED isn’t unusual, or if disabling it doesn’t seem straightforward, the EOD technicians use special-­purpose robots to place plastic explosives on it and blow it up. [In next month’s issue, IEEE Spectrum will publish a companion article to this one, on EOD in Iraq.]

There are other ways to neutralize an IED. A type of ”predetonator” used in Iraq emits a strong electromagnetic pulse that wrecks the integrated circuits in the cellphone or other appliance that triggers an IED. The pulse comes from a very high voltage capacitor discharging very suddenly. When its ICs are zapped, the trigger might ”fail open”—with no explosion—or it might ”fail closed,” detonating the IED.

Inevitably, there has been a countermeasure, and a cheap one at that. ”These are billion-dollar solutions with ten-cent countermeasures,” says Daniel B. Widdis, an instructor at the Naval Postgraduate School, in Monterey, Calif., who did a tour as an electronic countermeasures specialist in Iraq. [ Editor’s note: In response to JIEDDO’s request, IEEE Spectrum agreed not to disclose the countermeasure.]

More sophisticated predetonators are said to mimic the signals of the IEDs’ triggering devices in order to set them off. In the typical case the triggering devices, and therefore the specific codes that will trigger them, are not known. In an interview published in the 3 September 2007 issue of Aviation Week and Space Technology , James M. Smith, the CEO of EDO Corp., said that the predet systems transmit sequences of codes very rapidly. When the right code comes up, the IED detonates. The technique doesn’t work, however, if the code is long—say, 18 bits or more. There are simply too many possible combinations, Smith said.

In February, JIEDDO announced that it had canceled two big predetonator programs, code-named Alexis and Electraâ¿¿C, on the grounds that the signals from those systems interfered with counter-IED jammers such as Duke. A third program, called Blow Torch, is ongoing.

An article in the 25 March edition of The Scotsman newspaper, which quoted only anonymous sources, said that U.S. forces in Iraq and Afghanistan were using specially equipped Vietnam-era EA-6B Prowler aircraft to clear roads for convoys by transmitting appropriate signals to predetonate IEDs. (The article said the sweeps are called courtesy burns.)

A former JIEDDO official points to a tempting but difficult challenge for future predetonators. ”It would be a breakthrough if we could find a safe and effective way to predetonate blasting caps,” he says. ”To underline the difficulty, remember that industrial and mili­tary caps are designed to not react to the static electricity that creates lightning.”

How do you mitigate an IED blast? Today, mostly with armor. Over the past year and a half, contractors and soldiers have gone from 3-ton SUVs to 7.8-ton Revas, and from 5-ton Humvees to 25-ton MRAPs and JERRVs.

Of course, there are disadvantages. Tons of armor make vehicles too sluggish to speed away from an ambush. And simple physics and economics confirm that in an escalating contest between bombs and armor, it’s much cheaper and easier to make bigger bombs than to try to shield against those bombs with more and more armor.

But armor isn’t the only factor in the life-death equation. MRAPs and JERRVs are much higher off the ground than Humvees, and parts of their undercarriages are V-shaped. The V shape deflects the force of a blast under the vehicle outward, away from the vehicle. The increased height not only puts more distance between the passenger compartment and a bomb buried in the road, it also makes it more difficult for insurgents to target the passenger compartment with an explosively formed penetrator.

The first MRAPs were delivered to Iraq in January 2007; there are now more than 3200 of them in combat roles. There have been more than 150 IED attacks on MRAPs, the U.S. Defense Department says, which resulted in a total of eight deaths. All the fatal attacks involved either an EFP or a deep-buried IED. The Defense Department plans to spend $5.4 billion to buy 4000 more MRAPs, making this acquisition program the Pentagon’s third largest (only missile defense and the Joint Strike Fighter are bigger).

Future combat trucks will mitigate blasts with more than simple armoring. Some of the competing designs for the Joint Light Tactical Vehicle, the MRAP’s proposed more agile but no-less-blast-resistant successor, take inventive approaches. For example, to reduce the organ- and spine-crushing shock from a blast that comes from below, some JLTV designs suspend their seats from the ceiling, rather than bolting them to the floor.

”If I can vastly mitigate the effects of an attack, I would argue that that is defeating the IED, too,” says the Lexington Institute’s Gouré.

Over the past 5 years, during which the U.S. Department of Defense spent more than $13 billion on counter-IED efforts, the IED did in fact become less effective. But how much of that success is attributable to technology? And was the money well spent? The answers are elusive.

At the very outset of the IED problem in Iraq, in mid- to late 2003, with soldiers driving around in unarmored Humvees and contractors in unaltered SUVs, almost every IED attack caused a casualty. It now takes roughly six IED attacks to cause one coalition casualty, according to JIEDDO.

Slightly more than half of all IEDs are found and cleared without detonating, JIEDDO says. Of those that do detonate, roughly 40 percent of them cause no injuries. More heavily armored vehicles are behind that statistic. And the more technologically advanced JLTV promises further improvements in survivability.

There are other indications of progress. Insurgent groups typically pay people, usually freelancers who are just in it for the money, to emplace IEDs. Several years ago, the going rate was about $50 per IED. Today the rate is $200 outside Baghdad, and $400 to $500 inside Baghdad, according to a counter-IED training official in Iraq. The higher rates are believed to reflect, among other things, the increased risk and danger of the job.

JIEDDO director Metz believes the factors behind that fee increase suggest that the IED problem is solvable and also indicate the way forward. ”It’s constant pressure put on those who emplace IEDs that will win the day,” he says. ”It’s becoming a cost-ineffective and risky business to be in.”

How much more can technology contribute to that solution? To explain a lull in IED activity in Iraq in early 2008, JIEDDO’s most recent annual report pointed to several factors: the cooperation of thousands of ”concerned local citizens” who helped coalition forces locate IEDs and IED-making resources; the military surge, which stabilized some convulsive areas by pouring troops into them; and military efforts against the networks and ”event chains” that lead to IEDs on the roads. Less prominent in JIEDDO’s list are ­technology-related factors, a fact expounded on by defense affairs writer Sharon Weinberger in a Wired blog that was subtitled in part ”Tech barely a factor.”

Few of the people in Iraq whose job it is to deal with IEDs would embrace that assessment. They wouldn’t deny that it’s their eyes and intuition, along with local intelligence, that uncover most IEDs. But traveling Iraq’s roads regularly makes them more appreciative of things like jammers, Gyrocams, EOD robots, armor, infrared and other sensors, and useful intel distilled with the help of a computer program from maybe half a dozen sources.

Without a doubt, many big-budget projects and exotic technologies have fizzled or were quickly and cheaply countered by the insurgents. But that doesn’t mean that some of the technologies under development now or deployed in secret aren’t already working, or that others won’t be part of a more effective set of responses in the next few years.

It doesn’t even mean that pursuing each and every one of those ultimately unsuccessful projects was a mistake. ”Defeating the system takes leader­ship,” says Lt. Col. Jeremy G. Mansfield, director of Canadian Forces EOD. ”That’s why we pay the generals the big bucks. It takes risk. Some things are going to cost a lot of money, and they aren’t going to work. Get over it.”

The Lexington Institute’s Gouré believes that a combination of technolo­gies, including some yet to be fielded, along with more survivable vehicles, aggressive exploitation of intelligence, and adherence to good operational counter­measures (simply varying the routes taken on repeated missions, for instance) might get the rate of IED detonations down to 15 or 20 percent from the present 40. That might be good enough.

”You want to get to a rate that’s tolerable for you but unacceptable to him,” he says. ”I suspect that’s exactly how it will end.”

And don’t dismiss what’s been achieved so far, Gouré says. With new tactics and technologies in both ­counter-IED and EOD, ”the American military has invented, in about three or four years, a way of warfare that didn’t exist before. That’s lightning speed.

”Could they be less bureaucratic?” he asks. ”Probably not. That’s the way the system works.”